| Contracting Parties/Signatories | Signature | Instrument | In Force | Details |
| Andorra | September 6, 1952 | Ratification: December 31, 1952 | September 16, 1955 | Details |
| Argentina | September 6, 1952 | Ratification: November 13, 1957 | February 13, 1958 | |
| Australia | September 6, 1952 | Ratification: July 24, 1969 | | |
| Austria | September 6, 1952 | Ratification: April 2, 1957 | | |
| Belgium | December 30, 1952 | Ratification: May 31, 1960 | August 31, 1960 | Details |
| Bolivia (Plurinational State of) | | Accession: December 22, 1989 | March 22, 1990 | |
| Bosnia and Herzegovina | | Declaration / Notification of Succession: July 12, 1993 | March 6, 1992 | |
| Brazil | September 6, 1952 | Ratification: October 13, 1959 | January 13, 1960 | |
| Cambodia | | Accession: August 3, 1953 | September 16, 1955 | |
| Canada | September 6, 1952 | | | |
| Chile | September 6, 1952 | Ratification: January 18, 1955 | September 16, 1955 | |
| Costa Rica | | Accession: December 7, 1954 | September 16, 1955 | |
| Cuba | September 6, 1952 | Ratification: March 18, 1957 | June 18, 1957 | |
| Czech Republic | | Declaration / Notification of Succession: March 26, 1993 | January 1, 1993 | |
| Denmark | September 6, 1952 | Ratification: November 9, 1961 | February 9, 1962 | |
| Ecuador | | Accession: March 5, 1957 | June 5, 1957 | |
| El Salvador | September 6, 1952 | | | |
| Finland | September 6, 1952 | Ratification: January 16, 1963 | April 16, 1963 | |
| France | September 6, 1952 | Ratification: October 14, 1955 | January 14, 1956 | Details |
| Germany | September 6, 1952 | Ratification: June 3, 1955 | September 16, 1955 | Details |
| Ghana | | Accession: May 22, 1962 | August 22, 1962 | |
| Greece | | Accession: May 24, 1963 | August 24, 1963 | |
| Guatemala | September 6, 1952 | Ratification: July 28, 1964 | October 28, 1964 | |
| Haiti | September 6, 1952 | Ratification: September 1, 1954 | September 16, 1955 | |
| Holy See | September 6, 1952 | Ratification: July 5, 1955 | October 5, 1955 | |
| Honduras | September 6, 1952 | | | |
| Hungary | | Accession: October 23, 1970 | January 23, 1971 | |
| India | September 6, 1952 | Ratification: October 21, 1957 | January 21, 1958 | |
| Ireland | September 6, 1952 | Ratification: October 20, 1958 | January 20, 1959 | |
| Israel | December 16, 1952 | Ratification: April 6, 1955 | September 16, 1955 | |
| Italy | September 6, 1952 | Ratification: October 24, 1956 | January 24, 1957 | |
| Japan | January 3, 1953 | Ratification: January 28, 1956 | April 28, 1956 | |
| Kenya | | Accession: June 7, 1966 | June 7, 1966 | |
| Lao People's Democratic Republic | | Accession: August 19, 1954 | September 16, 1955 | |
| Lebanon | | Accession: July 17, 1959 | October 17, 1959 | |
| Liberia | September 6, 1952 | Ratification: April 27, 1956 | July 27, 1956 | |
| Liechtenstein | | Accession: October 22, 1958 | January 22, 1959 | |
| Luxembourg | September 6, 1952 | Ratification: July 15, 1955 | October 15, 1955 | |
| Mauritius | | Declaration / Notification of Succession: August 20, 1970 | March 12, 1968 | |
| Mexico | September 6, 1952 | Ratification: February 12, 1957 | May 12, 1957 | |
| Monaco | September 6, 1952 | Ratification: June 16, 1955 | September 16, 1955 | |
| Montenegro | | Declaration / Notification of Succession: April 26, 2007 | June 3, 2006 | |
| Morocco | | Accession: February 8, 1972 | May 8, 1972 | |
| Netherlands | September 6, 1952 | Ratification: March 22, 1967 | June 22, 1967 | |
| New Zealand | | Accession: June 11, 1964 | September 11, 1964 | Details |
| Nicaragua | September 6, 1952 | Ratification: May 16, 1961 | August 16, 1961 | |
| Norway | September 6, 1952 | Ratification: October 23, 1962 | January 23, 1963 | |
| Pakistan | | Accession: April 28, 1954 | September 16, 1955 | |
| Panama | | Accession: July 17, 1962 | October 17, 1962 | |
| Paraguay | | Accession: December 11, 1961 | March 11, 1962 | |
| Peru | December 2, 1952 | | | |
| Philippines | | Accession: August 19, 1955 | November 19, 1955 | |
| Portugal | September 6, 1952 | Ratification: September 25, 1956 | December 25, 1956 | Details |
| Rwanda | | Accession: August 10, 1989 | November 10, 1989 | |
| San Marino | September 6, 1952 | | | |
| Serbia | September 6, 1952 | Declaration / Notification of Succession: September 11, 2001 | April 28, 1992 | Details |
| Slovakia | | Declaration / Notification of Succession: March 31, 1993 | January 1, 1993 | |
| Slovenia | | Declaration / Notification of Succession: November 5, 1992 | June 25, 1991 | |
| Spain | September 6, 1952 | Ratification: October 27, 1954 | September 16, 1955 | |
| Sri Lanka | | Accession: July 27, 1988 | July 27, 1988 | |
| Sweden | September 6, 1952 | Ratification: April 1, 1961 | July 1, 1961 | |
| Switzerland | September 6, 1952 | Ratification: December 30, 1955 | March 30, 1956 | |
| the former Yugoslav Republic of Macedonia | | Declaration / Notification of Succession: April 30, 1997 | November 17, 1991 | |
| Tunisia | | Accession: March 19, 1969 | June 19, 1969 | |
| United Kingdom | September 6, 1952 | Ratification: June 27, 1957 | September 27, 1957 | Details |
| United States of America | September 6, 1952 | Ratification: December 6, 1954 | September 16, 1955 | Details |
| Uruguay | September 6, 1952 | Ratification: January 12, 1993 | April 12, 1993 | |
| Venezuela (Bolivarian Republic of) | | Accession: June 30, 1966 | September 30, 1966 | |